@jcmayer3 , before you run and dive into following @MaryK4 advice to file as MFS ( for your spouse ) -- I generally would agree with her advice but with some pre-work.
(a) Please read through this from Washington DC DOR --> https://otr.cfo.dc.gov/sites/default/files/dc/sites/otr/publication/attachments/2019%20D-40_Booklet....
(b) since you would have to buy DC state software anyways, consider preparing the return both ways ( MFJ ) and MFS, with allocating only spousal Washington DC income to be taxed by Washington. This shoud allow you to make an informed decison
(c) Note that unless your spouse has officially given up MI residency ( driver's license, voter reg, home etc. etc. ) Michigan would still expect the earlier residency still valid ( despite temporary sojourn in another state ), will tax world income ( based on federal AGI ) and then give credit for any taxes paid to Washington DC.
There is more here than meets the eye and mostly depends on your longer term plan
If you have more on this please feel welcome to add comments and I will come back and clarify
